A vector sensitive latch is described in U.S. Pat. No. 3,820,741 and this latch was used in the Apollo-Soyuz Test Program docking/berthing system. That system incorporated three latches fastened to a docking/berthing ring and automatically released if the mating ring was not fully captured and separated by a set amount. In the fully captured condition, a small clearance between the latch roller and the mating docking/berthing ring was required to ensure that the latch would set. Structural latches were thus provided to remove the clearance and to preload the mating rings in order to prevent separation. Not only was a second set of latches required but in addition means to activate and release the second set of latches thus incorporating additional unnecessary weight and complexity to that particular system.
In a pending U.S. Patent Application by inventor, William R. Acres, assigned to the same assignee as the present case, Ser. No. 783,888, filed Oct. 3, 1985, and entitled "Preloadable Vector Sensitive Latch", there is described a system that relates to a preloadable vector-sensitive latch which automatically releases when the force vector from a latch member reaches a specified release angle. In addition, it contains means to remove clearance between the latched members and to preload the latch to prevent separation at angles less than the specified release angle.
The latching mechanism of that invention overcomes the problem of the prior capture latches in that it is easily released when there is an improper seating because of a novel linking means which creates favorable vector considerations relating to the load and the latch member. These same vector considerations also overcome the problem of releasing a fully seated docking mechanism, in that the load need not be relieved in order to release the latching mechanisms and in fact the presence of a load on that latch member actually facilitates the uncoupling of the docking mechanism.
U.S. Pat. Nos. 2,662,276, 3,075,800, 707,246, and 2,885,010 show rods with pivoting fingers and biasing means for the fingers, which are designed to be inserted within a cylindrical cavity such as a pipe and the like in order to provide means to grasp the pipe from the inside and apply a longitudinal pulling force.
U.S. Pat. Nos. 3,742,807 and 2,365,787 show rods with expandable fingers for inserting into aligned holes within, and maintaining a spaced relationship between adjacent parts.
U.S. Pat. Nos. 1,166,284 and 2,523,519 show fingers that pivot from a rod in order to grasp the inside of a pipe. Both patents show screw actuated means for providing a longitudinal force.
U.S. Pat. Nos. 3,508,723 and 4,018,409 have application to the capturing of spacecraft. The first shows means for locking one spacecraft onto another through the rocket nozzle by means of pivoting locking shoes. The latter shows a docking device in the form of a manipulator arm capable of expanding inside a specially designed docking receptacle.
None of the above references, however, disclose the complete combination herein particularly the use of a traveling sleeve to, first, protect and retain the spring loaded toggle fingers and, second, to release and activate them. Also none teach the rigid attachment of a grapple fixture for retrieving a spacecraft.